More than 60,000 starlings fly over Utrecht

The sky above Utrecht neighbourhood Hoograven, was the site of a strange phenomenon Wednesday. Approximately 60,000 to 70,000 starlings took flight in a large cloud of symmetrical shape and form.

Such a large flock of birds over an urban area is extraordinary, said a spokesperson from the Dutch organisation for the protection of birds.

Adding to the spectacle are two of the neighbourhoods resident peregrine falcons who live in the area where the starlings rest, and are “regularly snacking,” said the spokesperson. Peregrine falcons are known to prey on starlings.

According to the spokesperson, the starlings have been in a swarm above Hoograven for the past few weeks, but over the last few days more birds have joined the cloud, making it an unusual size.

The large clouds of starlings can be a nuisance. The city of Utrecht reported Wednesday seven reports of nuisance filed in 2011. Most of these were related to noise and excrement.

Starlings join groups from late summer to early spring. As they skim through the air together they gain protection from birds of prey which become disoriented by their fast moving formations. The probability of an individual starling being caught by prey in such a cloud is very small, says the spokesperson.

When breeding season begins coupling starlings will retreat to nests. By the end of the summer their young are grown and the birds return to their groupings.